Remove mbed-os-example-client

This example is now deprecated and as such needs to be removed from
ci test compilation.

tools/test/examples/examples.json

@@ -55,22 +55,6 @@
       "export": false,
       "auto-update" : true
     },
-    {
-      "name": "mbed-os-example-client",
-      "github":"https://github.com/ARMmbed/mbed-os-example-client",
-      "mbed": [
-          "https://os.mbed.com/teams/mbed-os-examples/code/mbed-os-example-client"
-      ],
-      "test-repo-source": "github",
-      "features" : [],
-      "targets" : ["Freescale_EMAC", "NUVOTON_EMAC", "NXP_EMAC", "RZ_A1_EMAC",
-                   "STM_EMAC"],
-      "toolchains" : [],
-      "exporters": [],
-      "compile" : false,
-      "export": false,
-      "auto-update" : true
-    },
     {
       "name": "mbed-os-example-sockets",
       "github":"https://github.com/ARMmbed/mbed-os-example-sockets",